Migration of the developing testis to and through the
internal inguinal ring is at least partly dependent on the
development of elevated intra-abdominal pressure by the
abdominal musculature. Without this pressure, the processus
vaginalis may not extend into the scrotum and the testis
will not be pushed into the inguinal canal. Cryptorchidism
occurs in all boys with the Prune Belly Syndrome (lax
abdominal wall musculature) and it is more common in boys
born with abdominal wall defects that result in a decrease
in intra-abdominal pressure (gastroschesis,
oomphalocele).

Diagnosis: Examination of a newborn will demonstrate any abdominal
wall defects. Many of these boys will have non-palpable gonads
present in the abdominal cavity.

Treatment: Orchiopexy (the surgery to bring the testis into the
scrotum). This surgery may require a relatively extensive dissection
in the retroperitoneum to locate and mobilize the testis.